Activated effects after combat damage

Question

I am looking for some rules clarification on the sub steps during attacks.

Q1a- I am told that Reconnaissance can be used AFTER combat damage has been dealt to an opponent, thus granting your creatures a pseudo vigilance. Can this be done even without additional Combat-triggers to respond to? (Something about gaining priority after damage?)

Q1b- Does the same rulings work with Berserk. To destroy unwanted creatures of my opponents after they deal damage?

Q2- How does Berserk on one of your own creatures interact with Maze of Ith or Reconnaissance? Are you able to prevent a creature from being destroyed? Or will Berserk's effect still trigger because said creature is still marked as having attacked at all?

Answer 1

Question 1A

Reconnaissance can in fact be activated after combat damage. The reason for this is because after damage is dealt, all players receive priority before creatures are removed from combat.

Question 1B

Berserk contains the text

Cast this spell only before the combat damage step

So you wouldn't be able to cast it after the creature deals damage regardless. This seems self explanatory to me, so if I'm missing part of your question's intent, please let me know.

Question 2

The gathering ruling on Reconnaissance reads,

Does not undo any effects that triggered on declaration of attackers or blockers.

I interpret this to mean that anything that triggers or depends upon a creature having attacked will still be in effect. Regardless of if the creature is no longer attacking, it still has been declared as an attacker, meaning that the creature would still be destroyed by Berserk. Maze of Ith WOULD follow the same logic, except that it doesn't actually remove the creature from combat. Instead, it reads,

Untap target attacking creature. Prevent all combat damage that would be dealt to and by that creature this turn.

Maze will have no impact on Berserk whatsoever, although it is worth noting that even if it removed a creature from combat, it still would not save a creature targeted by Berserk.

Answer 2

506.1. The combat phase has five steps, which proceed in order: beginning of combat, declare attackers, declare blockers, combat damage, and end of combat.

Players recieve priority (have the ability to cast spells and use abilities) in each step, after the event the step is named after happens. (So, in the declare blockers step, all blockers are declared, then players can cast spells.)

511.3. As soon as the end of combat step ends, all creatures and planeswalkers are removed from combat. After the end of combat step ends, the combat phase is over and the postcombat main phase begins (see rule 505).

Reconnaissance has no timing restrictions, but it can only target attacking creatures. Per rule 511.3, a creature stays attacking until the End of Combat Step ends. That means that you can get the vigilance effect you want by using Reconnaissance during the Combat Damage Step (because the damage happens before priority) or during the End of Combat Step (because the creature stays attacking until after priority)

Berserk, on the other hand, reads "Cast this spell only before the combat damage step." You can't cast it after damage had been dealt.